1. Field of the Invention
The present invention relates to a fusible link unit adapted to be accommodated in an in-vehicle electrical connection box. More specifically, the present invention relates to a fusible link unit including a bus bar, the bus bar forming a raw power supply circuit to be connected to a battery. The present invention provides a safety measure for such a bus bar.
2. Description of the Related Art
Bus bars are generally accommodated inside a case of an in-vehicle electrical connection box. Each of the bus bars is formed into a required shape by blanking a conductive metal sheet, thereby, serving as an internal circuit.
Among the bus bars, there is a bus bar which is connected to a battery without interposing a fuse therebetween. In other words, such a bus bar is connected to a raw power supply circuit. Since a high current of 100 amperes or more flows through such a bus bar, in the event that a tool or the like erroneously falls when installing the electrical connection box to the vehicle and a cover or an upper wall of a housing accommodating the bus bar therein is damaged, the bus bar may become exposed, whereby a short circuit may occur.
For example, as shown in FIGS. 6A and 6B, a bus bar 5 to be connected to a raw power supply circuit includes a fusible link and is accommodated in a fuse box 1 arranged on a side surface of a battery, and an upper cover 6 is placed thereover (see, e.g., JP-A-2001-256878).
The bas bar 5 is formed such that a primary bus bar portion 2, a secondary bus bar portion 3 and a fuse element 4 are formed in a one-piece structure, and battery attaching portions 2a of the bas bar 5 are directly attached to the battery. The battery attaching portions 2a are accommodated in the fuse box 1 without being molded.
With the fuse box 1 that is configured as described above, in the event that a tool or the like falls on the cover 6 and breaks the same when installing the fuse box 1 on a vehicle, the battery attaching portions 2a of the bus bar 5 may become exposed, whereby a short circuit or an electric leak may occur.